Esterification stearic acid

Esterification over Amberlyst BD20 was evaluated by processing a model mixture in a fixed-bed reactor. The model reaction mixture was prepared by dissolving 10 wt.% of pure stearic acid (> 97%, Fluka, Germany) in a low-acid vegetable oil (0.04 %) bought in the supermarket. Methanol (> 99.5%) was used without any preliminary treatment. 

The ratio of the a- to the j -anomeric D-glucosyl ester can be influenced by changing the reaction conditions. In DMF the a-anomer of the crocetin bis(D-glucosyl ester) was formed in about 70% yield.[196] Esterification of D-glucose with the imidazolides of benzoic acid or stearic acid in pyridine furnished a mixture of the a- and j -anomers of the C(l) glucosyl ester.[196]... 

Chemat et al. [35] examined rates of esterification of stearic acid by butanols as a model reaction to compare differences between homogeneously and heterogeneously catalyzed reactions, Scheme 10.1. Particular attention was paid to whether the effect of microwaves can be advantageously used to improve yields and to accelerate the rate of esterification. 

Scheme 10.1 Esterification of stearic acid with 1-butanol.

Esterification of stearic acid and acetic acid with propanol and butanol in the presence of Fe2(S04)3/KSF montmorillonite [37]. The rate enhancement observed (1.5-2.5 times) was ascribed to the higher temperature of the catalyst bed (calculated to be 9-18 K above the bulk temperature). Reaction conditions batch (no stirring) and a stirred single-mode tank reactor, catalyst particle size 5 mm, 10-fold excess of alcohol. 

Pentaerythritol Ester As with glycerol esters, the esters are produced by esterification of pentaerythritol with the desired fatty acids. For example, under defined reaction conditions and use of stearic acid in defined concentration, pentaerythritol distearate has been recently developed as an off-white wax with very weak odor (Cutina PES). This type of product is offered as co-emulsifier and consistency factor for cosmetic products with high sensorial elegance and can be applied in various formulations (Fig. 4.17). 

The hyperbranched polyesteramides described above can also easily be functionalized by esterification with various mono carboxylic acids like acetic acid, benzoic acid, 2-ethylhexanoic acid, stearic acid, (un)satuxated fatty acids, or (meth)acrylic acid. With the exception of the latter mentioned acids, which give highly temperature sensitive products, the synthesis of these functionalized hyperbranched polyesteramides can be performed in two different ways ... 

By coupling an ultrasonic probe with a microwave reactor and propagating the ultrasound waves into the reactor via decalin introduced into their double jacket design, Chemat et al. studied the esterification of acetic acid with propanol and the pyrolysis of urea to afford a mixture of cyanuric acid, ameline and amelide (Scheme 9.19)136. Improved results were claimed compared to those obtained under conventional and microwave heating. The MW-US technique was also used to study the esterification of stearic acid with butanol and for sample preparation in chemical analysis137,138. 

Chemat, F., Poux, M. and Galema, S.A., Esterification of stearic acid by isomeric forms of butanol in a microwave oven under homogeneous and heterogeneous reaction conditions, /. Chem. Soc., Perkin Trans. 

Nakamura et al. (1986) Batch Esterification of triolein using stearic acid Lipase from Rhizopus delemar... 

Liang et al. (1998) Continuous Inter-esterification of palm oil by stearic acid Lipase from Mucor miehei... 

Nakamura et al. (1990) studied the esterification of triolein with stearic acid using four different lipases Mucor miehei, Rhizpous delmar, Alcaligenes sp. and Rhizopus japonicus. They varied the water content of the system... 

Glyceryl Behenate Glyceryl behenate is a mixture of glycerides of fatty acids which is obtained by esterification of glycerin with behenic acid. It may also contain arachidic acid, stearic acid, erucic acid, lignoceric acid, and palmitic acid. It is available as a waxy mass or powder, possesses a faint odor, and is white in color. It is... 

Amorphous Sn-, Si-, and Al-containing mixed oxides with homogeneous elemental distribution, elemental domains, and well-characterized pore architecture, including micropores and mesopores, can be prepared under controlled conditions by use of two different sol-gel processes. Sn-Si mixed oxides with low Sn content are very active and selective mild acid catalysts which are useful for esterification and etherification reactions [121]. These materials have large surface areas, and their catalytic activity and selectivity are excellent. In the esterification reaction of pentaerythritol and stearic acid catalytic activity can be correlated with surface area and decreasing tin content. The trend of decreasing tin content points to the potential importance of isolated Sn centers as active sites. 

Lipase-catalyzed esterification of fatty acids with alcohols [oleic acid + ethanol (141, 152, 163, 169, 178, 195-197), oleic acid + oleyl alcohol (144, 179, 198-200), lauric acid + butanol (142), myristic acid + ethanol (138, 139, 143, 201), stearic acid + ethanol (202), anhydrous milkfat fatty acids + ethanol (197)] in SCCO2 has been widely studied to understand the kinetics/mechanism of the reaction and to determine the effect of operating conditions, substrate concentration, and water content on enzyme activity. Alternative catalysts such as p-toluenesulfonic... 

Glyceryl palmitostearate is manufactured, without a catalyst, by the direct esterification of palmitic and stearic acids with glycerol. 

Derivation Alcoholysis of stearin or esterification of stearic acid with butanol. 

Sorbitan is derived from sorbitol by dehydration and then esterified with fatty acids as described for PGME. Depending on the amount of fatty acids used for esterification the equilibrium reaction mixture may contain primarily sorbitan monoesters or triesters. Sorbitan esters of palmitic or stearic acid crystallize from melt in a stable a-like crystal form. 

Esterification of stearic acid with lactic acid (minimum 88% pure) in the presence of sodium or calcium hydroxide (or carbonate) results in a mixture of stearoyl lactylates (sodium or calcium salts), fatty acid salts and free fatty acids. The main component is a stearoyl monolactyl ester but esters containing di-, tri- and poly-lactic acids are also present. 

The HLB value of stearic acid is 17.0 and would vary with esterification or salification. Because of the surfactant features discussed above, stearic acid and its esters are widely used in pharmaceutics. 

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